Mechanisms Underlying Activity-Dependent Interneuron Development

活动依赖性中间神经元发育的潜在机制

• 批准号: 8515526
• 负责人: Natalia Vanesa De Marco Garcia
• 金额: $ 8.94万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-23 至 2013-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8515526
• 关键词: Ablation; Action Potentials; Advisory Committees; Affect; Applications Grants; Area; Award; Axon; Brain; Cajal-Retzius cells; Calcium; Candidate Disease Gene; Cells; Characteristics; Communities; Cues; Defect; Dendrites; Development; Development Plans; Disease; Educational process of instructing; Educational workshop; Electrophysiology (science); Electroporation; Environment; Epilepsy; Etiology; Excision; GABA Receptor; Gene Targeting; Genetic; Genetic Programming; Glutamate Receptor; Glutamates; Goals; Grant; Human Pathology; Image; Individual; Institutes; Interneurons; Laboratories; Link; Maps; Marketing; Mediating; Methods; Molecular Biology; Morphology; Mus; N-Methyl-D-Aspartate Receptors; Nature; Neurobiology; Neurologic; Neurons; Neurosciences; Neurotransmitters; Occupations; Output; Pathogenesis; Pathology; Pathway interactions; Pattern; Phase; Physiological; Play; Population; Positioning Attribute; Postdoctoral Fellow; Process; Pyramidal Cells; Radial; Readiness; Research; Resolution; Role; Schizophrenia; Science; Shapes; Signal Pathway; Signal Transduction; Sodium; Somatosensory Cortex; Source; Staging; Synapses; Techniques; Time; Training; Vasoactive Intestinal Peptide; Viral; Work; Writing; abstracting; autism spectrum disorder; calretinin; career development; cohort; design; developmental genetics; gamma-Aminobutyric Acid; improved; in utero; in vivo; inhibitory neuron; interdisciplinary collaboration; medical schools; migration; nervous system development; neuron component; neuronal excitability; neuropsychiatry; postnatal; programs; receptor; relating to nervous system; research study; skills; transmission process; virus genetics

DESCRIPTION (provided by applicant): This application is for the K99/R00 Pathway to Independence award. I am currently a senior postdoctoral fellow in the Fishell lab at the NYU-School of Medicine and I have an extensive background in molecular biology and mouse genetics. My career development plan is designed to acquire theoretical and practical training in electrophysiology under the guidance of Drs. Gord Fishell and Bernardo Rudy. In addition, the development plan is aimed at strengthening my presentation, grant-writing and teaching skills. A postdoctoral advisory committee (PAC) will oversee my progress and assess my readiness to enter the job market and make the transition to an independent laboratory. Finally, I will take courses and workshops to develop a background in neurological and neuropsychiatric disease entities with the goal of improving my ability to consider my research findings in the context of potential links to human pathologies. The K99 portion of the award would take place within the Smilow Neuroscience Program at NYU-School of Medicine. This program, in combination with the larger Neuroscience community at NYU (Center for Neural Science and Skirball Institute), will provide a superb academic environment in which to complete my training and successfully transition to an independent academic position. Scientific Abstract: Recent experimental evidence has revealed that intrinsic genetic programs endow GABAergic interneurons with an early subtype identity. It is also known that interneurons participate in correlated network activiy during development. Indeed, my previous work indicates that the radial migration and morphological development of calretinin and reelin but not vasoactive intestinal peptide interneurons, the major subtypes derived from the caudal ganglionic eminence (CGE), are activity-dependent. Furthermore we have found that glutamatergic drive is essential for mediating the activity required for the proper development of axons and dendrites towards the end of the first postnatal week. However, the mechanisms by which activity regulates interneuron maturation are not fully understood. This proposal is aimed at revealing the identity of the neuronal types that provide interneurons with the neurotransmitters necessary for laminar targeting, and for the proper formation of axons and dendrites (Aim 1). In addition, this project will explore the role of glutamate receptors in morphological development (Aim 2). Finally, a long-term aim of this research plan is to describe the connectivity pattern of developing interneurons as they integrate into cortical circuits, and to assess how neuronal activity may regulate the process by which this pattern is generated (Aim 3). A variety of neuronal cohorts populate the cortex during the first postnatal week, when activity-dependent maturation of interneuron subtypes takes place. Glutamatergic cell cohorts present during this time include Cajal-Retzius cells, glutamatergic transient cells, subplate cells and pyramidal cells. Due to thei spatial and temporal distribution, these cohorts are well suited to provide interneurons with the glutamatergic drive that is fundamental for their morphological development. Glutamate release from each individual cohort will be genetically blocked to assess the impact of these populations on interneuron maturation (Subaim 1a). GABAergic transmission is also prominent at early stages of cortical development and may contribute to laminar targeting. To assess the role of GABA in radial migration, GABA receptors will be blocked pharmacologically (Subaim 1b). While our previous experiments have indicated a requirement for glutamate in morphological development, the mechanism responsible for activity-sensitive maturation is not understood. Due to the developmental role of NMDA receptors, our experiments will focus on the study of these ionotropic receptors during interneuron development. The cell-autonomous consequences of NMDA receptor removal in CGE interneuron will be assessed. Our analysis will also include the study of the signaling pathways operating downstream of these receptors (Aim 2). After interneurons undergo migration and develop characteristic morphologies, they integrate into cortical circuits. However, the identity of synaptic inputs to specific subsets of CGE interneurons are unknown. Monosynaptic viral tracing techniques will be used in combination with in utero electroporation to reveal the pattern of connectivity of maturing interneurons (Subaim 3a). In addition, our experiments will assess the impact of perturbing neuronal activity on the integration of interneurons into nascent cortical circuits (Subaim 3b). The experiments in this grant proposal will be carried out in vivo in the mouse somatosensory cortex. The principles that will emerge from these studies, however, are expected to apply to other regions of the cortex as well. A better understanding of interneuron development and GABAergic circuit formation over a potentially broad set of cortical areas is likely to contribute to our understanding of the pathogenesis of diseases in which interneuron defects are thought to play a role. In addition, the experimental approach presented in this proposal exemplifies the advantage of interdisciplinary collaboration within the field of neurobiology. Indeed, it is my conviction that the integration of both the conceptual approach and experimental techniques from two particular subfields, developmental genetics and electrophysiology, will continue to advance our understanding of CNS function and pathology.

描述（由申请人提供）：本申请适用于 K99/R00 独立之路奖。我目前是纽约大学医学院 Fishell 实验室的高级博士后研究员，在分子生物学和小鼠遗传学方面拥有广泛的背景。我的职业发展计划旨在在博士的指导下获得电生理学的理论和实践培训。戈德·费舍尔和贝尔纳多·鲁迪。此外，该发展计划旨在加强我的演讲、资助写作和教学技能。博士后咨询委员会 (PAC) 将监督我的进展并评估我进入就业市场和过渡到独立实验室的准备情况。最后，我将参加课程和研讨会，以发展神经学和神经精神疾病实体的背景，目的是提高我在与人类病理学潜在联系的背景下考虑我的研究结果的能力。该奖项的 K99 部分将在纽约大学医学院的 Smilow 神经科学项目内进行。该项目与纽约大学（神经科学中心和斯基博尔研究所）更大的神经科学社区相结合，将为我完成培训并成功过渡到独立学术职位提供极好的学术环境。科学摘要：最近的实验证据表明，内在遗传程序赋予 GABA 能中间神经元早期亚型身份。还已知中间神经元在发育过程中参与相关网络活动。事实上，我之前的工作表明，钙视网膜蛋白和 reelin 的径向迁移和形态发育是活动依赖性的，但血管活性肠肽中间神经元（源自尾神经节隆起 (CGE) 的主要亚型）却不是。此外，我们发现谷氨酸驱动对于调节轴突和树突在产后第一周末正常发育所需的活动至关重要。然而，活动调节中间神经元成熟的机制尚不完全清楚。 该提案旨在揭示神经元类型的身份，这些神经元类型为中间神经元提供层状靶向以及轴突和树突的正确形成所需的神经递质（目标 1）。此外，该项目将探讨谷氨酸受体在形态发育中的作用（目标2）。最后，该研究计划的长期目标是描述发育中的中间神经元融入皮质回路时的连接模式，并评估神经元活动如何调节这种模式的生成过程（目标 3）。 在出生后的第一周，当中间神经元亚型发生活动依赖性成熟时，各种神经元群聚集在皮质中。在此期间存在的谷氨酸能细胞群包括 Cajal-Retzius 细胞、谷氨酸瞬时细胞、底板细胞和锥体细胞。由于它们的空间和时间分布，这些群体非常适合为中间神经元提供对其形态发育至关重要的谷氨酸驱动。每个群体的谷氨酸释放都将被基因阻断，以评估这些群体对中间神经元成熟的影响（Subaim 1a）。 GABA 能传递在皮质发育的早期阶段也很突出，可能有助于层流靶向。为了评估 GABA 在径向迁移中的作用，将从药理学角度阻断 GABA 受体 (Subaim 1b)。虽然我们之前的实验表明形态发育需要谷氨酸，但负责活性敏感成熟的机制尚不清楚。由于 NMDA 受体的发育作用，我们的实验将重点研究这些离子型受体在中间神经元发育过程中的作用。将评估 CGE 中间神经元中 NMDA 受体去除的细胞自主后果。我们的分析还将包括对这些受体下游运作的信号通路的研究（目标 2）。中间神经元经历迁移并形成特征形态后，它们整合到皮质回路中。然而，CGE 中间神经元特定子集的突触输入的身份 未知。单突触病毒追踪技术将与子宫内电穿孔结合使用，以揭示成熟中间神经元的连接模式（Subaim 3a）。此外，我们的实验将评估扰动神经元活动对中间神经元整合到新生皮质回路中的影响（Subaim 3b）。 本拨款提案中的实验将在小鼠体感皮层体内进行。然而，这些研究得出的原理预计也适用于大脑皮层的其他区域。更好地了解潜在广泛的皮质区域的中间神经元发育和 GABA 能回路形成可能有助于我们了解中间神经元缺陷被认为发挥作用的疾病的发病机制。此外，该提案中提出的实验方法例证了神经生物学领域内跨学科合作的优势。事实上，我坚信，整合 来自两个特定子领域（发育遗传学和电生理学）的概念方法和实验技术将继续增进我们对中枢神经系统功能和病理学的理解。